Ya this guy is really nice. Ice creams pretty darn good too

It's funny you bring up cost. If you're in the water sector you know the biggest impediment to dealing with non revenue water is the cost of pipe replacement vastly outweighs the value of lost water. My utility estimates we lose around 10-20% of our water to leaks/old pipes, which amounts to several million dollars a year in lost revenue and billions of gallons of water. That sounds insane right? Of course the cost of fully replacing all the past service life lines is in the billions, thus the driver for spending all the capital is tough to sell to rate payers. As water professionals it's our job to evaluate the best health outcomes for our customers against the reality of infrastructure costs that rate payers will accept. Basically if the solution someone is peddling for improving water security involves building a bunch of pipelines (eg. piping Mississippi out west) there's almost always a more economical alternative.

DPR has a huge value proposition in many areas because you can avoid a ton of cost from additional distribution infrastructure. Comparing the non-potable reuse system (purple pipe) in California, which is estimated to cost 8k/acre-ft, while building a full scale water purification plant like San Diego is around $500-$600/acre foot. This compares very favorably against desalination ($1000>), ipr and especially building new reservoirs (which in drought stricken areas really doesn't do much good).

I see some folks have brought up phaceuticals and other trace chemicals, another great benefit is dpr systems using UF to RO will exclude most of these organic compounds, pfas included.

Of course in places where water scarcity isn't a driver, added treatment systems will be excessive, but there are increasingly regions of the country experiencing long term drought and the need to secure stable water supply. In many cases, the costs make sense